A Program Project of this magnitude will require the coordination of personnel and technical expertise. The main functions of the Administrative Core will be to facilitate communication between the five laboratories involved in the proposed studies. This will entail development and maintenance of a shared database, statistical consultations, the solicitation of input from the Advisory Committee, and organization of an annual meeting of all participants in the Program Project. In addition, Core A will assist in issues related to the budget, distribution of animals and tissues, maintain regular contact with the Project Officer at NIA, and prepare annual progress reports/renewal applications. In Years 04 and 05, Core A will coordinate the planning of future directions of this Program Project and oversee preparation of the application for competing renewal. Five Specific Aims are proposed: 1. To facilitate communication between all participating investigators, all members of the participating laboratories including graduate students and postdoctoral fellows, and investigators and Advisory Committee. 2. To establish and maintain data management system that will facilitate exchange of samples and data between the participating laboratories and maximize utilization of every animal. 3. To provide statistical support and consultations for experimental design and data analysis, and to identify and recommend statistical approaches for combined analysis of data from different Projects/Cores. 4. To provide assistance and oversight of fiscal management of projects and Core B and of exchange of animals, tissues and other samples (plasma, tissue extracts, mRNA or cDNA preparations) between laboratories. 5. To prepare annual progress reports and coordinate preparation of a competing renewal application. RELEVANCE (See instructions):